1. 
   Fractionally
   Frac'tion·al·ly adverb By fractions or separate portions; as, to distill a liquid fractionally , that is, so as to separate different portions.
   Found op http://www.encyclo.co.uk/webster/F/70
   
   
2. 
   Fractionally
   • (adv.) By fractions or separate portions; as, to distill a liquid fractionally, that is, so as to separate different portions.
   Found op http://thinkexist.com/dictionary/meaning/fractionally/
   
   

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